An (inner) hypervisor running as Virtual Machine (VM) on top of an (outer) hypervisor is a powerful kind of software container for a guest Operating System (OS) running within the inner hypervisor. One use case of this is when the enterprise Information Technology (IT) administrator wants to reduce the operational cost of the VM by running the VM in the cloud, while maintaining the service in the VM available all the time. A solution is for the enterprise IT administrator to live migrate a VM from a server on-premises to a server off-premises leased from a cloud data center provider. Moreover, the server on-premises may run a given hypervisor brand, whereas the server in the cloud may run a different hypervisor brand.
An instance of the source hypervisor brand (used on-premises) is created as an inner hypervisor-VM on the destination hypervisor in the cloud data center, forming two “nested hypervisor instances”. The original VM may then be live-migrated from the on-premise server to the inner hypervisor-VM in the cloud datacenter. This solution is practical because running a generic VM on two nested hypervisors is supported, to various degrees, in commercially available hypervisors.